pm_createPolicy

Create a new sponsor policy. The caller's MegaNode identity (derived from the Bearer JWT) is automatically set as the policy owner.

Notes:

• maxGasCost is always initialised to 0 at creation time. Fund the policy afterwards via the deposit API.
• Each sponsor may own at most N policies (default 5, configurable by the platform).
• The Authorization: Bearer <jwt> header is required.